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1	Evalutation of Different Fermentation Medthods on the Yield and Cost Effectiveness for Recombinant HDGF Production Wang, Jin-kye 03 August 2009 (has links) HDGF (hepatoma-derived growth factor) is a novel growth factor,identified from conditioned medium of hepatoma cell line. HDGF has growth stimulating activity for fibroblast and some hepatoma cells. HDGF, a novel defined growth factor with mitogenic effect, has homology protein sequence as HMG (high mobility group) protein and their three dimension structures appeared to be similar to each other. Recently, elevated HDGF expression was found in developing kidneys but less was found in adult kidney. In addition, HDGF expression was found to be correlated with angiogenic status of tissues. Thus, it is speculated that HDGF plays a role during embryonic development and angiogenesis. HDGF also plays a role in cell-cell interaction and cell migration. HDGF is a growth factor that is involved in stimulating vascular smooth muscle cells (SMCs)proliferation during development and in disease. HDGF contains a true bipartite nuclear localization sequence necessary for nuclear targeting. HDGF is sciential factor in stimulating DNA replication and cell proliferation of vascular smooth muscle cell.In this study,we used E. coli strain BL21 (DE3) to express the recombinant protein hepatoma derived growth factor(HDGF). To find out the optimal production conditions,we studied on the different temperature and fermentor to calculate all cost . HDGF Plasmid BL21 IPTG Ampicillin E. coli
2	Orthogonality and Codon Preference of the Pyrrolysyl-tRNA Synthetase-tRNAPyl pair in Escherichia coli for the Genetic Code Expansion Odoi, Keturah 2012 May 1900 (has links) Systematic studies of basal nonsense suppression, orthogonality of tRNAPyl variants, and cross recognition between codons and tRNA anticodons are reported. E. coli displays detectable basal amber and opal suppression but shows a negligible ochre suppression. Although detectable, basal amber suppression is fully inhibited when a pyrrolysyl-tRNA synthetase (PylRS)-tRNAPyl_CUA pair is genetically encoded. trnaPyl_CUA is aminoacylated by an E. coli aminoacyl-tRNA synthetase at a low level, however, this misaminoacylation is fully inhibited when both PylRS and its substrate are present. Besides that it is fully orthogonal in E. coli and can be coupled with PylRS to genetically incorporate a NAA at an ochre codon, tRNAPyl_UUA is not able to recognize an UAG codon to induce amber suppression. This observation is in direct conflict with the wobble base pair hypothesis and enables using an evolved M. jannaschii tyrosyl-tRNA synthetase-tRNAPyl_UUA pair and the wild type or evolved PylRS-tRNAPyl_UUA pair to genetically incorporate two different NAAs at amber and ochre codons. tRNAPyl_UCA is charged by E. coli tryptophanyl-tRNA synthetase, thus not orthogonal in E. coli. Mutagenic studies of trnaPyl_UCA led to the discovery of its G73U form which shows a higher orthogonality. Mutating trnaPyl_CUA to trnaPyl_UCCU not only leads to the loss of the relative orthogonality of tRNAPyl in E. coli but also abolishes its aminoacylation by PylRS. Pyl, pyrrolysine PylRS, pyrrolysyl-tRNA synthetase NAA, noncanonical amino acid aaRS, aminoacyl-tRNA synthetase T4 PNK, T4 polynucleotide kinase AzF, para-azido-L-phenylalanine PCR, polymerase chain reaction RF, release factor TrpRS, tryptophanyl-tRNA synthetase ArgRS, arginyl-tRNA synthetase Trp, tryptophan Lys, lysine Glu, glutamate Gln, glutamine Phe, phenylalanine Arg, arginine.

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Evalutation of Different Fermentation Medthods on the Yield and Cost Effectiveness for Recombinant HDGF Production

Orthogonality and Codon Preference of the Pyrrolysyl-tRNA Synthetase-tRNAPyl pair in Escherichia coli for the Genetic Code Expansion